Normaalijännityksiä

Normaalijännityksiä is a Finnish term that translates to "normal stresses" in English, referring to a specific type of stress experienced by a material. It is a force acting perpendicularly to a surface area. This is distinct from shear stress, which acts parallel to the surface. When a material is subjected to a load, internal forces develop within it, and these forces can be resolved into components acting normal and tangential to any imagined internal surface.

Normal stresses can be either tensile or compressive. Tensile stresses occur when a material is pulled apart, tending to elongate it. For example, a rope under tension experiences tensile normal stress. Compressive stresses, on the other hand, arise when a material is squeezed or pushed together, tending to shorten it. A pillar supporting a load experiences compressive normal stress.

The magnitude of normal stress is calculated by dividing the normal force acting on a surface by the area of that surface. The unit of stress in the International System of Units (SI) is the pascal (Pa), which is equivalent to one newton per square meter. Higher stresses can lead to deformation or failure of the material. Understanding normal stresses is fundamental in fields such as mechanical engineering, civil engineering, and materials science for designing safe and reliable structures and components.